NAVIOR-24S
™
Appendix D
NMEA 0183 Communication Interface
177
NAVIOR-24S ™
Revision
V1.00 20.05.2008
DTM – Datum Reference
Local geodetic datum and datum offsets from a reference datum (in the receiver it always from
WGS84).
Latitude and longitude offsets from the reference datum are positive numbers, altitude offset may be
negative. Offsets change with position: position in the local datum is offset from the position in the
reference datum in the directions indicated:
_
_
local datum
ref
datum
P
P
offset
=
+
_
local datum
P
- position in the used local geodetic datum;
_
ref
datum
P
- reference datum position.
Format:
$GPDTM, ccc, a, x.x, a, x.x, a, x.x, ccc <CR><LF>
Field
Format
ccc Local
datum:
W84 = WGS84
P90 =
ПЗ
-90
S42 =
СК
42
S95 =
СК
95
999 – user defined
a
Local datum subdivision code:
A, P = local datum #1
B = local datum #2
C = local datum #3
D = local datum #4
x.x, a
Latitude offset, min, N/S
x.x, a
Longitude offset, min, E/W
x.x
Altitude offset, m
ccc
Reference datum W84 = WGS84
<CR><LF>
2 ASCII control characters
